Improvement in metal alloys for commercial coin



UNITED STATES PATENT OFFIos.

WILLIAM WHEELER HUBBELL, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN METAL ALLOYS FOR COMMERCIAL COIN.

Specification forming part of Letters Patent .No. 191,146, dated May 22,1877; application filed April 4,1876.

Melt them separately and pour them together,

and, in mixing, add one grain of sulphate of sodium or sulphate ofpotassium to one thousand grains of the metal. The alloy metal isslightly heavier than the mean of the component metals, which makes itpeculiarly valuable for coin, not easily counterfeited. At the same timea dollar of the alloy is very much less in size than a silver dollar.The proportions may be slightly varied. The silver may be increased tothirty parts to one of gold, and decreased to twenty parts to one ofgold. The

I copper may be increased to one-eighth, and

decreased to one-twelfth. But the most per feet or maximum affinity isestablished in the proportions of one of gold, twenty-four of silver,and two and a half of copper.

The alloy metal free from flaws shows a density 10.802, and with flaws10.710. The mean density of the several metals is 10.685. and the alloymetal shows an increase in value or weight or density of .025 to .117.Usually gold and silver alloyed are less in density than the mean oftheir constituents.

This alloy of gold, silver, and copper, within these proportionsspecified, owing to its great density and intrinsic value, is especiallyvaluable or suited for coin-dollars and fractions of a dollar. v

I claim as my invention The alloy coin metal of gold, silver, andcopper, substantially in the proportions and for the purpose described.

WM. WHEELER HUBBELL.

Witnesses:

THOMAS C. GoNNoLLY, A. E. BEEOHER.

